1. Field of the Invention (Technical Field)
The present invention relates to collimation and beam alignment methods and apparatuses and to liquid crystal devices ("LCTV's").
2. Background Art
Adaptive optics systems employing LCTV's include those described in Kirsch et al., "Modulation characteristics of the Epson liquid crystal television", Optical Engineering 31:5, pp. 963-967 (May 1992); Bonaccini et al., "Adaptive optics wavefront corrector using addressable liquid crystal retarders", SPIE Current Developments in Optical Engineering IV 1334, pp. 89-97 (Jan. 1990); Bonaccini et al., "Adaptive optics wavefront corrector using addressable liquid crystal retarders: II", SPIE Active and Adaptive Optical Components 1543, pp. 133-143 (Jan. 1991); U.S. Pat. No. 4,695,973, entitled "Real-Time Programmable Optical Correlator", to Yu (Sep. 1987); U.S. Pat. No. 4,943,709, entitled "Liquid Crystal Adaptive Optics System", to Grinberg et al. (Jul. 1990); U.S. Pat. No. 5,253,033, entitled "Laser Radar System with Phased-Array Beam Steerer", to Lipchak et al. (Oct. 1993); and U.S. Pat. No. 5,113,282, entitled "Dual Light Valve System with Selective Decoupling of Light Valves", to O'Meara et al. (May 1992). However, it is believed that no one has heretofore applied LCTV's to the problem of beam alignment and collimation.